BLOW UP TANKS WITH C-4!!:
When you have to blow up a tank and you dont have any rocket launchers, take your C-4 and have it out then have another team member, or you, throw a smoke bomb right next to it then the person with the C-4 runs to the tank and you have to get all the way against it then crouch down and and face it put one piece of C-4 on it then throw another smoke bomb and when it covers the tank or makes it so it cant see then get on your feet and run back to your team members then detonate the C-4.

Beating the last level:
Ok when you get to the very last level put some mines in front of the building so when the guy runs out he will die and you wont have to run after him and kill him. Do all that before you use your laser.

Beating The Tank Level (You get to use):
First you have to get all the rockets in the first part of the level. Then take the tank and blow up the tank shooting at you, just after the first barricade. If you look just off to the right there is a pass that will bring you to the closest tank. Look to the right and blow up that tank too. First tank, throw a smoke grenade then run up plant the C-4 and run! Do the same thing for the second one parallel to the first. If you look directly after the second non-blocked tank there is a pass that ends at the cliff. Destroy the tank and the guy. Turn around and go left down the road. BE CAREFUL!!! A tank is waiting for you around the corner. Destroy that tank with yours then move on. The rest of the level shouldn't give you much trouble. Good Luck!!!!

Heal Dead People:
When one of your people die, right when they fall get your medikit. go over to him and it will say, "heal" press the A button it will heal them almost all the way.